The surface proteins of the gonococcal outer membrane appear to be an important constituent of the interaction between gonococci and the mucosal epithelium of the human host. Although pili most likely initiate the interaction between the organism and the host environment, many of the invasive characteristics of gonococci can not be attributed to these appendages. The major outer membrane protein and the opaque protein may be linked to these invasive properties. We plan to explore the functional characteristics of these two proteins. The opaque protein is similar to the ompA of E. coli. OmpA has been implicated in side-to-side stabilization of conjugation much like the opaque protein has been described as the "intercellular glue" of the gonococcus. The oligosaccharides of LPS seem to be an important part of this adhesive property. We first want to explore further the structural and functional similarity between the opaque protein and ompA and then determine if the LPS oligosaccharide or a similar host derived oligosaccharide moiety is the receptor for this protein. We have found that the major outer membrane protein may be transferred from the surface of the gonococcus to other membranes. Such a transfer would introduce an aqueous channel in the recipient membrane and cause a leakage of ions and loss of membrane potential. With the use of "lipophilic ion probes" and ESR, we will verify such a transfer and the conditions necessary for such an event to occur and its consequences. The loss of membrane potential of the cells of the epithelium may explain why these cells seem to actively engulf gonococci and transport them to the lamina propria.